1. Field of the Invention
The present invention relates to a job history information auditing system, which can record job history information including an execution user and a date and time of execution in association with a scan job, copy job, print job, and the like executed in an image forming apparatus.
2. Description of the Related Art
Along with the recent popularization of printers and digital MFPs (Multi-Function Peripherals), print, copy, and sending operations of originals can now be easily executed. However, although user convenience is enhanced, information leakage resulting from the print, copy, and sending operations of originals pose a problem. As a measure against this problem, a digital MFP, which saves job history information in a storage device upon execution of a print job, copy job, FAX job, and e-mail sending job, is available.
A job history information auditing system includes the digital MFP and a server. A database is built on the server. Job history information recorded in the digital MFP is sent to the server, and is saved in the database. Pieces of job history information for a predetermined period are saved on the database in a searchable state. For example, when information leakage has been uncovered, the pieces of job history information corresponding to the information leakage can be traced back. Such digital MFP and job history information auditing system require large-capacity storage areas to save a large number of pieces of job history information. For this reason, a method of reducing the required storage capacity and efficiently saving more job histories has been proposed.
For example, in Japanese Patent Laid-Open No. 2006-330939, when identical image data is to be input/output to/from an image processing apparatus, reference information to the image data already saved in the database is saved in place of the full image data. In this way, the storage capacity required for the database is reduced. More specifically, the image processing apparatus records image data at the time of execution of an input job, and records reference information to the image data at the time of execution of an output job that uses the already input image data. This mechanism will be referred to as a link log hereinafter.
The method of Japanese Patent Laid-Open No. 2006-330939 will be described in more detail below. The digital MFP has an area for saving document data in the apparatus to have, for example, a name “user BOX”. Then, even when the user does not have data at hand, he or she can execute a print or e-mail sending job using the document data saved in the user BOX. In this case, an input job is a job that saves document data in the user BOX, and an output job is a job that uses the document data in the user BOX. Since the identical document data is processed by the input and output jobs, it is redundant to save image data in the database as job history information at the respective times of execution of the input and output jobs. For this reason, image data is saved in the database only at the time of execution of the input job, and only reference information to the image data saved in the database is saved at the time of execution of the output job. In this way, the data size saved in the database can be reduced.
Japanese Patent Laid-Open No. 2007-148830 has proposed a printing system, which suppresses information leakages by traceably saving keywords, items of print job attributes, and the like that match extraction conditions associated with time information as job history information. In this system, extraction conditions of tracing information are set in advance in association with time periods. Tracing information that matches extraction conditions, which change depending on time periods, is extracted from print data according to a print execution time, and is saved. In this way, conditions required to record job history information in a normal service time period and those required to record job history information in a time period other than the normal service time period can be defined, thus allowing operations in consideration of, for example, a network load.
By combining the link log mechanism required to reduce the storage area and the job history information recording stop time period setting mechanism required to reduce the network load, respective problems can be solved.
However, when these two mechanisms are combined, image data may leak from the job history information in some cases. More specifically, when an input job is executed in a job history information recording stop time period, this job history information is not recorded. That is, image data is not saved in the server. However, using reusable image data saved in the digital MFP by the input job, an output job can be executed in a job history information recording time period. In this case, a link log including a link to image data, which is not saved in the server, is saved in the server as job history information. As a result, it is not possible to confirm image data to be reused upon auditing job history information. For this reason, a problem is posed for the job history information auditing system, which aims at enhancing security such as information leakage suppression.